Method of expanding sheet metal.



I H. B. CHESS, JR.

METHOD 0F EXPANDING SHEET METAL.

APPLICATION FILED JAN. 21, 1913.

Patented Apr. 22, 1913.

3 SHEETS-SHEET 2.

A TTORNE Y H. B. CHESS, JE. METHOD 0E EXPANDING SHEET METAL.

AEPLIGATION FILED 1111.21, 1913.

' Patented Apr. 22, 1913.

3 SHEETS-SHEET 3.

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inaiirnn srarns PATENT orribili.

HARVEY B. CHESS,JR., OF PITTSBRGH, PENNSYLVANIA.

METHOD F EXPANDING" SHEET METAL.

Specification of Letters Patent.

T o all 'whom t may concern.'

' Be it known thatl I, HARVEY B. CHESS, J r., a citizen of the' United States, and a resident of Pittsburgh, Allegheny county, State of Pennsylvania, have'invented an Improvement in Methods of Expanding Sheet Metal,

l of which the following is a specification.

My method of expanding sheet metal consists essentially in rst slitting the sheet to form strands connected by unslit portions, stretching or elongating the strands thus l Jformed, and deploying or pulling away from one .another the stretched strands to form open meshes bounded by the stretched panded -metal of that form in which ex-l panded strips alternate with `unexpanded raisedy ribs, as the formation of the ribs in l the unexpanded portions of the sheet may be utilized to impart the lateral tension for deploying or spreading the cut and stretched strands to form the open meshes.

InA the drawings: Figure 1 is a plan view "of a piece of metal that has been subjected y to the preliminary slitting; Fig. 2 is a cross V35,11; Fig. 3A is a plan view of the same sheet section of the same on the line A--A of Fig.

, shown in Fig. l after the strands have been stretched or expanded; Fig. 4 is a cross sec- 'tion on'the li'ne B-B of Fig. 3; Fig. 5 is a plan view ofthe same sheet shown in Figs.

1 and 3 after it has been opened or deployed; Fig. 6 is a cross section on the line C-'-`C of Fig. 5; Figs. 7 and 8A are diagrammatic views showing the action of the dies in1 bending and stretching the strands to bring the sheet into the condition shown in Figs. 3 anda; Figs. 9 and 10 are diagrammatic views showing'the action of thedies in opening or deploying the sheet to Vbring it into `the completed condition shown 'in Figs. 5,

and; 6; Fig. 11 is av front elevation of'aportion of the expanding dies showing their action in stretching, expanding, or elongating the strands; and ,Fig. 12 is a perspective view of four adjacent lines of stretched or expanded strands before they have beendeplayed or opened' out to form meshes.

, and the connecting portions j.

A sheet of metalfz is First slitted in the manner shown in Figs. l and 2 to form a plurality of rows of short parallel slits Y) with the slits in alternate posit-ions in successive rows. Such slittingl of a 4sheet has been common practice in some methods of making expanded metal', and may be effected Patented Apr. 22, 1913. v

Application filed January 21, 1913. Serial No. 743,241.

by passingl the sheet between suitable cutting rolls.

I have illustrated my process as applied to making sheets of expanded metal having parallel expanded portions with intermediate unexpanded raised ribs, and,` therefore,

.the slitted portions b are made in parallel4 strips separated by intermediate unslitted strips c, which lat-ter are formed into` the ribs 7c as is hereafter explained. If, howv ever, the sheet is to be expanded throughout,

without the intermediateiribsit will -be slit continuously, z'. e. without any intermediate unslit portions. After the sheet is thus slit it is placed between ex andingdies, such as are indicated in Figs. and 8, to stretch or expand the st-rands e, e', which are formed by theslits. As shown, I employ upper and lower setsy of dies f, g,composed of plates arranged side by side in contact. These diesv act together to bend, and at the same time, to stretch, expand or elongate the strands e, e', oppositely, z'. e. all the strands while all the strands in the next row are bent Aand stretched downwardly. To e'ect this result the dies- Vare formed 'with complementary scalloped edges f', g', with the scallops projecting in opposite direct-ions in adjacent pairs of dies. In Fig. 11 the dies f and g are slightly separated. These' outer dies act tostretch downl the row of met-al strands upon which they act, while the dies of the next pairact to stretch up the row of strands upon which they act. At the same time the connecting portions of metal 7' between the slits are, bent into an inclined osisition, as shown at j in Figs. 3, 4, 9 an 12;

lthis is effected by beveling the coactin faces ofthe dies f and g between the sca loped portions, as shown at f2, g2, in Figs. 7 and 11. When the met-al strands have thus been stretched or elongated they are 'deployed or spread apart by pulling the edges of the sheet laterally to form open meshes bounded by the stretchedor expanded strands e, e So far as concerns the process broadly this lateral expension cor deploying. of the stretched and in one row are bent, and stretched upwardly expanded metal may be effected by any means; but, when the metal is to be made into sheets having expanded strips separated b v unexpanded raised ribs, as shown in Figs. 5 and 6, the lateral expansion or deploying may be effected by dies o, p, as shown in Figs. 9 and l0. lThese dies act upon the uncut and unexpanded portions c, c and apply the lateral pull or tension which deploys or opens up the cut and stretched strands into the expanded form, at the same time forming the intermediate raised ribs My invention is not limited to any particular mechanism or mechanical means for performing the process, and those mechanical devices shown and described are to be taken merely as illustrative of such devices as may be used for the purpose; for example, it is immaterial to my invention, considered broadly, whether the slitting and stretching operations are performed successively or simultaneously. The essential features of my invention are that the sheet is slit to form strands arranged alternately in adjacent rows, that the strands so formed v'are stretched or elongated and are then drawn apart or deployed to produce an expanded body, the expansion of which consists both in the longitudinal stretching of the strands and in the lateral spreadingof the sheet to form open meshes.

Vhat I claim is as follows:

l. The method of expanding sheet metal, which consists in slitting the sheet in parallel lines of interrupted slits arranged 'alternately in adjacent lines, stretching longitudinally the metal of the strands formed by the rows of slits, and pulling the sheet laterally to deploy the stretched strands into open meshes.

2. The method of expanding sheet metal, which consists in slitting the sheet in parallel lines of interrupted slits arranged alternatelyin adjacent lines, stretching longitudinally the metal of the strands formed by the rows of slits transversely to the plane of the sheet, andpulling the sheet laterally to deploy the stretched strands into open meshes.

3. The method of expanding sheet metal which consists in slitting a 'portion of the sheet in parallel lines of interrupted slits arranged alternately in adjacent lines, stretching longitudinally the metal of the strandsformed by the rowsof slits, and bending the unslit portions of the sheet in a transverse plane to impose lateral tension on the slit and stretched portions and deploy them to form openmeshes.

4. The method of expanding sheet metal which consists in slitting the sheet in parallel lines of interrupted slits arranged alternately in adjacent lines, stretching longitudinally the metal of the strands formed by t-he rows of slits, bending into an inclined position the unslit portions connecting the slits, and pulling the sheet laterally to deploy the stretched strands and the connecting unslit portions into open meshes.

In testimony of which invention, I hereunto set myhand.

HARVEY B. CHESS, JR IVitnesses JOHN OMMERT. 

